The Mini Astrophysical MeV Background Observatory (MAMBO) CubeSat mission for gamma-ray astronomy

The origin of the cosmic diffuse gamma-ray (CDG) background in the 0.3 - 10 MeV energy range is a mystery that has persisted for over 40 years. The Mini Astrophysical MeV Background Observatory (MAMBO) is a new CubeSat mission under development at Los Alamos National Laboratory with the goal of addressing this longstanding puzzle. The concept is motivated by the fact that, since the MeV CDG is relatively bright, only a small detector is required to make high-quality measurements of it. Indeed, the sensitivity of space-based gamma-ray instruments to the CDG is limited not by size, but by the locally generated instrumental background produced by interactions of energetic particles in spacecraft materials. Comparatively tiny CubeSat platforms provide a uniquely quiet environment relative to previous MeV gamma-ray science missions. The MAMBO mission will provide the best measurements ever made of the MeV CDG spectrum and angular distribution, utilizing two key innovations: 1) low instrumental background on a 12U CubeSat platform; and 2) an innovative shielded spectrometer design that simultaneously measures signal and background. Los Alamos is partnering with commercial vendors for the 12U CubeSat bus and ground station network, which we expect will become a new paradigm for low-cost, fast-turnaround space science missions. We describe the MAMBO instrument and mission concept in detail and present the expected scientific return.